[file-history] set target selection right before overwriting a session

No need to save target selection before calling a refresher, it can be done when a new session arrives.

platform/vcs-impl/src/com/intellij/openapi/vcs/history/FileHistoryPanelImpl.java

@@ -274,6 +274,10 @@ public class FileHistoryPanelImpl extends PanelWithActionsAndCloseButton impleme
 
   @CalledInAwt
   public void setHistorySession(@NotNull VcsHistorySession session) {
+    if (myTargetSelection == null) {
+      myTargetSelection = myDualView.getFlatView().getSelectedObjects();
+    }
+    
     myHistorySession = session;
     refreshRevisionsOrder();
     HistoryAsTreeProvider treeHistoryProvider = session.getHistoryAsTreeProvider();
@@ -428,7 +432,6 @@ public class FileHistoryPanelImpl extends PanelWithActionsAndCloseButton impleme
     ApplicationManager.getApplication().invokeAndWait(() -> {
       if (myInRefresh) return;
       myInRefresh = true;
-      myTargetSelection = myDualView.getFlatView().getSelectedObjects();
 
       mySplitter.revalidate();
       mySplitter.repaint();